Equalizing-discharge brake-valve.



No. 729,153. PATENTED MAY 26, 1903. G. H. FRASER & J? N. WEIKLY. EQUALIZING DISCHARGE BRAKE VALVE.

APPLICATION FILED JAN. 3, 1899.

N0 MODEL.

INVENTORS:

FIG. 72.

WITNESSES:

v By Atzorneys, m I

UNHED STATES PATENT fatented May 26, 1903.

OF ICE.

GEORGE HOLT FRASER, or nRooKLYN, NEW YORK, AND JAMES N. WEIKLY, OF JERSEY CITY, NEW JERSEY; SAID WEIKLY'ASSIGNOR TO SAID FRASER.

EQUALIZING-DISCHARG E BRAKE-VALVE.

SPECIFICATION formingpart of Letters Eatent N 0. 729,153, dated May 26, 1903-.

Application filed January 3, 1899. SerialNo. 701,089. (No modelf) scribed as applied to an engineers valve,

of the kind commonly known as the New York brake-valve, shown in the patent granted to Vaughn and McKee, No. %,290, dated August 29, 1893, although it will be understood that these improvements may be ap'-. plied to other valves than that taken as a convenient example for illustration. In valves of this class it is usual to exhaust from the train-pipe, holding the valve open until the desired reduction is obtained throughout the system and then closing .it. This requires a prolonged holding of the valve in the application position and entails the disadvantage that when the valve is closed or thrown to lap the forward rush of air, which is Suddenly checked by closing the valve, has no-mea'ns of escape and under its momentum backs-up in the forward part of the brake system, and

so raises the pressure as to release or kick' 01f the forward brakes, thus making it very diificult to accomplish a uniform and suitable application of the brakes, especially for a long train.

This invention aims to provide an improved discharge-valve in which an equalizing discharge can be accomplished and improved means for, availing of Lhe equalizing-discharge feature for any valve in a Simpler and better way than has heretofore been possible.

To this end in carrying out the present im provements an equalizing automatically-operating valve is provided which is adapted to open at a predetermined train-pipe pressure and automatically discharge from the train-pipe until the pressure falls below that which opened it, which valve is adapted to open in proportion to the extent of the excess pressure to be relieved from the trainpipe, so that the discharge is graduated in rapidity to suit varying requirements. The improved equalizing-valve consists of a cyl I inder or compartment receiving fluid-pressure from the train-pipe side of the engineers valve so long as such valve is in any of its operative positions other than the position of lap, so that the engineer can always tell from his train-pipe gage just the pressure which the train-pipe will carry when he ceases application and until he renews application or releases. The engineers' slide-valve is preferably constructed with ports reciprocal to the equalizing-valr e port or ports, both sets of ports being constructed to preserve communication and equal pressure between the train-pipe and equalizing-cylinder at all positions except lap, at which position the cylinder carries the train-pipe pressure at the time the valve was moved to lap, so that any elevation of pressure in the train-pipe due to rushing air or other cause will be at once checked by operation of the equalizing-valve, which preferably consists of a piston and valve-stem, the latter closing an egress-duct from the train-pipe and the former standing between the cylinder-pressure on one side, tending to close it, and the train'pipe pressure on the other side, tendingto openit, and free tomove'to equalize these two pressures according to the area of its respective faces, so that a slight excess of train-pipe over cylinder pressure will be required at the engineers valve before the equalizing-valve unseats.

In the accompanying drawings,-Figure 1 is a longitudinal section of a New York brakevalve equipped .with this invention, the view being cut on the line 1 l in Fig. 2 and showing the valve in the running position. Fig.

2 is a cross-section thereof, cut in the planes of the lines 2 2 of Fig. 1 and looking in the direction of the arrow. Fig. dis a cross-section cut on the lines 3 3 in Fig. 1 and looking l in the direction of the arrow. Fig. 4 is a face view of the slide-valve. Fig. 5 is a plan view of the valve-seat, the parts being in the positions shown in Fig. 1. Fig. 6 is a longitudinal section of the valve when in the lap position. Fig. 7 is a similar view showing the parts in the quick-release position. Fig. 8 is a fragmentary enlarged vertical section on the axis of the equalizing-valve. Fig. 9 is a fragmentary cross-section cut in the planes of Fig. 2 and on the same scale as Fig. 8. Fig. 10 is a diagrammatic plan of the seat, showing a slide-valve in dotted lines in the lap position. Fig. 11 is a similar View showing the slide-valve in the application position, and Fig. 12 is a similar view showing the slide-valve in a quick-release position.

Referring to the drawings, the general construction and operation of the type of engineers valve shown will be described.

A represents the train-pipe chamber, from which the pipe at leads to the brake system; B, the main reservoir pressure-chamber, from which the excess-valve 1) controls feed to the train-pipe; C, the discharge-port, controlled by the slide-valve c in the chamber B; D, the cut-0E cylinder, in which the piston d works to automatically stop discharge; E, the feedports in the seat e; F, the application-port in the valve; f, the reciprocal port in the seat; G, the discharge-port in the valve, coinciding with the port 0 in the seat; H, the cutoff port in the seat; g, the central valvechatnber; h, the slide-valve chamber; I, the cut-off seat; J, the emergency-ports; K, the emergency outlet-port; L, the valve-lever; Z, the cut-off shifter; M, the feed and slowrelease port, and m the stem of the piston d. These parts are of Well-knOWn construction, and in their usual operation the valve 0 is slid along the seat from the quick-release po: sition (shown in Fig. 7) to the running position,(shown in Fiar.1,) thelap position,(shown in Fig. 6,) the various graduating stages of the application position, (shown in Fig. 11,) and the emergency position. (Not shown, but in which the valve is at the opposite extreme to quick release and the train-pipe is in full communication with the exterior.) In quick release, as shown in Figs. 7 and 12, the portf is in free communication with chamber B, all otherports being closed except cut-0E port H, which is in communication with air through port J, passing forward and opening into port 0, so all pressure can escape from cylinder D and full pressure flow into the trainpipe to release the valves and restore piston d, thus returning cut-off I to the normal position. In the running position the valve moves backward until port M opens communication with ports E andf, permitting feed to the train-pipe past reducing-valve 12. Port F is then closed by cut-01f I and port G by seat 6, but. port H is in communication with portf through port J, so that train-pipe pressure and the pressure in cylinder D are in equilibrium.

pipe,its pressure and that of cylinder Dwould not be displaced. In application the slidevalve is moved until port F opens port f by passing in front of the cut-off I, at which time port Ghas opened into port 0 and escape of. air from the train-pipe is permitted. The cylinder D remains cut off during application, so that the piston d moves forward as the train-pipe reduces, thus advancing the cutolf I, which automatically closes port F and stops further release of train-pipe pressure. Further application can be effected by moving the valve until port F again passes the edge of the cut-off I, and so on, and lap can be returned to at any time. In emergency the valve is moved to the extreme backward position, in which ports Jcommunicate with portf and port K communicates with port 0, so that there is a large outlet from the trainpipe to outer air. In this position all other ports are closed.

For storage of air for the cut-off cylinder D a small reservoir is usually connected to the duct 0; but this is only to provide suflicient air-space, so that there maybe enough air for expansion in the cylinder D Without requiring that such space he formed in the valve-shell itself.

It will be seen that while the valve may be shifted to and from application there is no provision for taking care of the increasing pressure due to a forward rush of airin case the valve is suddenly thrown from application to lapin other words, that there is no equalizing or graduating with the valve, as described, and that it is therefore necessary to maintain the valve at application a long time in order to insure a uniform pressure throughout the system, and it is possible that IIO a sufficient pressure may be caused by the rushing air to throw 0% some of the forward brakes when the valve is closed.

The present invention provides for equalizing effects on such systems as this and enables the user to at once and instantly set the brake system at the pressure which he Wishes to employ for the application and restore the valve to lap, letting the system automatically adjust itself to the predetermined pressure, and provides certain other features of improvement, which will now be described according to their preferred form for application to the type of valve in question. In the means shown for accomplishing this an equalizing-chamber P, a relief oroutlet valve Q, and an escape-port R are provided, together with means for controlling or determining the pressure in chamber P, so that this may be set to operate the valve or permit its operation at the desired train-pipe pressure or to vary the pressure in the chambe'r P coincidentally with variations of that in the train-pipe. The chamber P, valve Q, and controlling means for these parts can be variously constructed and operated, as will be apparent to those skilled in this art; but preferably the chamber P is formed as a cylinder bored in a plug 19, which is externally screw-threaded, and screws into a screwthreaded hole q, tapped in the partition 7" between the ports andfof the valve-shell,the

ports 0 being bored large enough to admit the plug. The valve Q is preferably a tapering valve seating in the port B, so that the farther the valve opens the greater will be its outlet area. The port R is shown as formed by a transverse bore or core in the wall S of the valve-shell and a right-angle bore 5, coinciding with the axis of the plug 19 and serving as the seat for the valve Q. A piston T, fitting the open end of the cylinder P, carries a valve Q, so that the latter can be moved toward and from the seat under the influence of the pressures at opposite sides of the piston, the latter being free to move to equalize such pressures and being so differentiated in area at the valve side to require a slight excess of pressure at this side before the piston will move the valve off its seat, this differentiation being equal to the cross-sectional area of the seat, so that normally the valve Q will be held closed and when open will close as soon as a predetermined difference in pressure is reaced at the train-pipe side of the piston T relative to that of the opposite side thereof.

Means are provided for supplying pressure to, confining it in, and releasing it from the cylinder P as desired. Preferably and most conveniently the pressure for the cylinder P is taken from the train-pipe chamber A and the cylinder P is controlled by the slidevalve 0. A simple method for giving this is to provide a port U, leading from the seat e to the cylinder 1, and one or more ports V and W and a stop-face X on the slide-valve, reciprocal to the port U for controlling the equalizing-valve. As shown, the port V is arranged at one side of the adjacent port J of the valve 0, and the ports V and W and face X are in the same line, the port V having a lateral extension "U carried inwardly sufficient to communicate with the portf in the seat and the portW having a lateral extension opening into one of the ports J in the valve.

The ports shown are arranged to keep free communication between the cylinder P and the train-pipe at all positions of the valve except the lap position, at which latter position the face X completely closes the cylinder P against ingress or egress of pressure. In the running from that to the quick-release positions the portv isin communication with port f, and thus maintains equal pressure within the cylinder P and train-pipe chamber A, as shown in dotted lines in Figs. 5 and 12. As soon as the valve is moved from the running to the lap position the port U is closed by the face X, as shown in Figs. 6, 8, and 10, thus locking in the cylinder P the pressure which trainpipe chamber carried at the time of going to lap, so that this pressure maintains valve Q closed so long as a like pressure exists in the chamber A, because of the area of the seat s, where only atmospheric pressure is opposed to the valve Q. Should train-pipe pressure remain stationary or fall while at lap, the valve Q will remain seated. In moving from lap to application the port W opens the port U at or before the time that the port F opens to reduce train-pipe pressure and the port W maintains the port U open, so that there is continual communication between the cylinder P and train-pipe chamber A during allpositions of the valve from lap to emergency, thus during all such time insuring an equilibrium of pressure between the trainpipe and equalizing chambers. This is shown in Fig. 11, which shows the valve 0 in the position of graduated application, from which the next backward movement will bring emergency application.

With the construction of valve shown the automatic cut-off I usually employed will not interfere with the operation of the improved equalizing feature despite the continual advancing of the cut-off during both lap and application. The equalizingchamber will always be'in communication with the trainpipe except when the slide-valve is at lap, and consequently will always carry pressure enough to keep the valve Q closed except when the slide-valve has closed egress from the train-pipe and the pressure in the trainpipe chamber has been elevated by forwardly rushing air above that at which the equalizing was set by the act of throwing the slidevalve to lap. Any such elevation of trainpipe pressure due to air rushes or momentum will serve to overcome the pressure in cylinder P as soon as the predetermined differential at which the valve Q should open is passed and will push the piston T backward until an equilibrium of pressures is attained at its opposite sides, thus opening the valve Q to an extent proportioned to the increase of trainpipe pressure and permitting the rapid escape of this pressure until it falls to approximately that in the equalizing-chamber, whereupon the latter will close the valve Q and cut olf further reduction of train-pipe pressure in the chamber A. Should a further application be desired, the movement to the application position will at once establish an equilibrium between the pressures in the trainpipe and equalizing chambers and maintain it until the valve is again moved to lap, whereupon the equalizing-valve will take care of any rushes or increases in the train-pipe chamher, as before.

The construction described will be seen to be a simple means foraccomplishing an equalizing discharge and one which can be applied to the type of valve shown without any change in the construction thereof other than drilling, tapping, and grooving the present shell and valve for receiving and controlling the equalizing-valve and its cylinder.

The operation of a brake-valve with the improvement described will be so well understood that further description than that before given will be .nnnecessary. It will suffice to say that itwill only be necessary for the engineer to drop the train-pipe pressure in the chamber A or the equalizing-chamber P to that desired for the application and then place the slide-valve at lap, whereupon the equalizing-valve will take care of the system, secure a graduated and uniform reduction from the train-pipe, yield to the momentum of the forwardly-rushing air, and vary its outlet area according to the rise of pressure thereof in the chamber A and prevent any danger of releasing or kicking olf forward brakes by reason of a forwardly-rushing column of air being suddenly checked by closing the slide-valve to lap. It will be seen that while the ports for controlling the equalizingvalve constitute valve mechanism for the equalizing-chamber and are essentially the same in function as though formed on a separate valve their connection with the ordinary slide -valve c secures the operation of both the equalizing and the usual valves by one manipulation and without the addition of other parts than those now to be handled by the engineer; also, that the usual trainpipe-pressure gage, which for convenience may be said to be represented by the gagepipe w, Fig. 2, indicating the pressure in the chamber A at the time of throwing the slidevalve to lap, will enable the engineer to know the pressure at which the system is held by the equalizing-valve Q, as the pressure at the time of going to lap will be that of the chamber P, and therefore pressure in the trainpipe will be kept at approximately this pressure until the valve is moved to open communication between the train-pipe andequalizing chambers.

It will be seen that this invention provides improvements whereby an equalizing-discharge valve can be employed in a very simple, convenient, and economical manner with any fluid-pressure system, and it will be understood that the invention is not limited to any of the particular details of construction, arrangement, or combination hereinbefore set forth and shown as constituting the preferred form of the invention nor to its application to a particular type of engineers valve used as an example for illustrating the invention nor to the control of the equalizingvalve by the engineers valve or the supply of the equalizing-pressure from the trainpipe, as the invention can be availed of in whole or in part according to such adaptations or modifications as circumstances or the judgment of those skilled in the art may dictate without departing from the spirit of the invention. It will also be understood that the terms cylinder and piston as herein used and the technical terms referring to particular parts in the fiuid-pressure-brake art are not restricted in their meaning for the purposes of this application to the constructions of the parts so designated, but are intended to cover any well-known equivalents in either function or construction of the parts herein referred to, the terms pistons and cylinders being considered herein as including such equivaleuts,for example,as compartments and diaphragms which can be used with equal effect according to this invention.

What is claimed is- 1. In fluid-pressure brakes and the like, an engineers valve comprising a train-pipe compartment, a discharge, and a rectilinearlysliding valve proper for such compartment, in combination with an equalizing-valve for controlling the train-pipe pressure, an equalizing-chamber controlling said equalizingvalve, means supplying said equalizing-chamber with fluid-pressure from said train-pipe compartment throughout the time that the valve proper is at application position and means controlling the pressure in the equalizing-chamber, whereby the pressure in the equalizing-chamber can be supplied from the train-pipe compartment, and can be utilized to control the equalizing-valve against the pressure in said compartment.

2. In fluid-pressure brakes and the like, the combination with an engineers valve comprising a trainpipe compartment, a discharge, an automatic cut-off valve for terminating service application, and a valve proper for controlling the brake, exhausting direct from said compartment during service application, of an equalizing-valve for the trainpipe pressure, an equalizing-chamber for controlling the equalizing-valve, means supplying pressure to said chamber, means communicating between said chamber and the trainpipe compartment, and means controlling such communication.

3. In fluid-pressure brakes and the like, an engineers valve comprising a train-pipe compartment, a discharge and a valve proper for controlling the brakes, and an automaticallyoperating cut-off valve for terminating service application, in combination with an equalizing-valve for controlling train-pipe pressure, an equalizing-chamber foroperating the equalizing-valve, means for supplying pressure to such chamber, and means preserving a substantially uniform pressure within said chamber and compartment when said valve proper is moving from the application position to the lap position.

4. In fluid-pressure brakes and the like, a valve comprising a train-pipe compartment, a discharge, and a valve proper therefor, and exhausting directly from said compartment for service application, in combination with an equalizing-valve, an equalizing-chamber for operating such valve, means supplying pressure to such chamber, and means maintaining a practically uniform pressure within said compartment and chamber while said valve proper is in the quick-release position. 5. In fluid-pressure brakes and the like, a valve comprising a train-pipe compartment, a discharge, and a direct exhaust valve proper controlling the brake, in combination with a pressure operated valve passive during application position of said valve proper, and controlling discharge from said compartment, a pressure chamber for closing said valve, means normally maintaining a substantial equilibrium of pressure in said chamber and compartment, and means isolating said chamber against variation of pressure and permitting independence of pressure in said chamber and compartment upon sudden stoppage of discharge.

6. In fluid-pressure brakes and the like, a valve comprising atrain-pipe compartment, a discharge from said compartment-,and a valve proper therefor, in combination with an auxiliary discharge-valve for said compartment, means operated by the pressure in said compartment tending to open said auxiliary valve, an auxiliary pressure-chamber, means operated by the pressure therein tending to close said valve, and means varying pressure in said auxiliary chamber approximately in accordance with the variations of pressure in said compartment when said valve proper is dis charging from said compartment, whereby during such discharge said auxiliary valve will not operate, and means preventing va riation of pressure in the auxiliary compartment when said valve is to operate.

7. In fluid-pressure brakes and the like, the combination with an engineers valve having train-pipe compartment, discharge from said compartment, and a valve proper controlling discharge, and an automatic cut-off valve for terminating such discharge, of an auxiliary discharge-valve opened by the pressure in said compartment to discharge therefrom, an auxiliary pressure-chamber for closing said valve, a valve-port for admitting train-pipe pressure to said chamber during discharge from said compartment, carried by said valve proper, and isolating said chamber from the train-pipe when said auxiliary valve is to become operative.

8. In fluid-pressure brakes and the like, an engineers valve having a train-pipe compartment, and a rectilinearly-sliding valve proper for exhausting directly therefrom for service application, in combination with a valve Q for said compartment, a fluid-pressure chamber for operating said valve, Q, a port U for said chamber, and a port V carried by said valve proper and controlling admission of pressure thereto.

9. In fluid-pressure brakes and the like, an engineers valve having a train-pipe compartment, and a direct exhaust-valve proper therefor, in combination with a valve Q for said compartment passive during application position of said valve proper, a fluid-pressure chamber for operating said valve Q, a port U for said chamber, and a face X carried by said valve proper and confining pressure in said chamber during the lap position of said valve.

10. In fluid-pressure brakes and the like,an engineers valve having a train-pipev compartment, and a valve proper therefor, discharging directly from said compartment during service application, in combination with a valve Q for said compartment, a fluid-pressure chamber for operating said valve Q, and a port W carried by said valve for admitting pressure to said chamber from said compartment while said valve is at emergency.

11. In engineers valves, a valve-shell havin g achamber A, horizontal outlet 0 and vertical wall 1", and a rectilinearly-sliding valve proper, in combination with a cylinder 1) fixed in said wall 1', and having an internal chamber P, a valve operated by the pressure.

in said chamber, a port traversing said Wall and communicating with said chamber, and means supplying pressure to and releasing it from said chamber.

12. In an engineers valve, a shell comprising a train-pipe chamber A, main reservoirchamber B, and outlet 0, in combination with a rectilinearly-sliding valve proper c, a second valve Q, a pressure-chamber P, means operating the valve Q by the difierences in pressure between the compartment A and chamber P, and means simultaneously controlling the valve proper and the pressure in said chamber.

In witness whereof we have hereunto signed our names in the presence of subscribing witnesses.

GEORGE HOLT FRASER. JAMES N. WEIKLY.

Witnesses as to Fraser:

FRED WHITE, THOMAS F. WALLACE.

WVitnesses as to Weikly:

GARRETT H. VREELAND, J. HARVEY SWENARTON. 

